Prime Minister Benjamin Netanyahu urged Europe on Monday to do what it can to prevent its nationals from taking part in a flotilla scheduled to depart for Gaza in late May.
"This flotilla must be stopped," Netanyahu told European ambassadors in Jerusalem
The Cyprus-headquartered international Free Gaza movement and other pro-Palestinian organizations plan to send more than 15 ships to Gaza.
They are scheduled to set sail around the anniversary of last year's lethal interception by Israel of the "Freedom Flotilla."
Israeli naval commandos shot dead nine civilian activists on the Turkish Mavi Marmara passenger ship on May 31, 2010.
The commandos said they felt their lives were endangered as they were taken by surprise by a group of several dozen activists, who used sticks and knives to stop the Israelis from boarding the ship.
The organizers charged the Israelis opened fire with no justification. Several soldiers were wounded.
The nine dead activists included Turkish nationals and an American of Turkish descent.
Israel stopped the flotilla in international waters, after organizers declared they would break its naval blockade of the Strip.
"If Israeli authorities thought that their attack on Freedom Flotilla 1 last year would break our momentum and scare us away from sailing to Gaza again, they were wrong," Free Gaza said in a statement on its website.
"We are now organizing Freedom Flotilla 2, scheduled to set sail in late May 2011, with twice as many vessels as we had last year."
Flotilla organizers hope to break through Israeli border controls and deliver supplies to the Gaza Strip.
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